Method and apparatus for adapting a channel sensing threshold

ABSTRACT

Methods and apparatuses for adapting a channel sensing threshold in a wireless communication system operating with shared spectrum channel access. A method for operating a base station (BS) includes determining whether an antenna configuration for channel sensing is omni-directional or directional and determining a channel sensing threshold. The channel sensing threshold includes two parts: a first part of the channel sensing threshold being common for omni-directional and directional antenna configurations and a second part of the channel sensing threshold depending on the antenna configuration. The method further includes performing a channel sensing procedure based on the antenna configuration and the channel sensing threshold and transmitting downlink (DL) data over a channel based on the channel being sensed as idle in the channel sensing procedure.

CROSS-REFERENCE TO RELATED APPLICATIONS AND CLAIM OF PRIORITY

This application is a continuation of U.S. patent application Ser. No.17/248,613, filed on Jan. 29, 2021, which claims priority to U.S.Provisional Patent Application No. 62/969,848, filed on Feb. 4, 2020 andU.S. Provisional Patent Application No. 62/976,461, filed on Feb. 14,2020. The content of the above-identified patent document isincorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates generally to wireless communicationsystems and, more specifically, the present disclosure relates toadapting a channel sensing threshold in a wireless communication system.

BACKGROUND

5th generation (5G) or new radio (NR) mobile communications is recentlygathering increased momentum with all the worldwide technical activitieson the various candidate technologies from industry and academia. Thecandidate enablers for the 5G/NR mobile communications include massiveantenna technologies, from legacy cellular frequency bands up to highfrequencies, to provide beamforming gain and support increased capacity,new waveform (e.g., a new radio access technology (RAT)) to flexiblyaccommodate various services/applications with different requirements,new multiple access schemes to support massive connections, and so on.

SUMMARY

The present disclosure relates to wireless communication systems and,more specifically, the present disclosure relates to adapting a channelsensing threshold in a wireless communication system.

In one embodiment, a base station (BS) in a wireless communicationsystem operating with shared spectrum channel access is provided. The BSincludes a processor configured to determine whether an antennaconfiguration for channel sensing is omni-directional or directional anddetermine a channel sensing threshold. The channel sensing thresholdincludes two parts: a first part of the channel sensing threshold beingcommon for omni-directional and directional antenna configurations and asecond part of the channel sensing threshold depending on the antennaconfiguration. The processor is further configured to perform a channelsensing procedure based on the antenna configuration and the channelsensing threshold. The BS also includes a transceiver operably connectedto the processor. The transceiver is configured to transmit downlink(DL) data over a channel, if the channel is sensed as idle in thechannel sensing procedure.

In another embodiment, a method of a BS in a wireless communicationsystem operating with shared spectrum channel access is provided. Themethod includes determining whether an antenna configuration for channelsensing is omni-directional or directional and determining a channelsensing threshold. The channel sensing threshold includes two parts: afirst part of the channel sensing threshold being common foromni-directional and directional antenna configurations and a secondpart of the channel sensing threshold depending on the antennaconfiguration. The method further includes performing a channel sensingprocedure based on the antenna configuration and the channel sensingthreshold and transmitting DL data over a channel based on the channelbeing sensed as idle in the channel sensing procedure.

In yet another embodiment, a user equipment (UE) in a wirelesscommunication system operating with shared spectrum channel access isprovided. The UE includes a processor configured to determine whether achannel sensing threshold is configured, determine whether an antennaconfiguration for channel sensing is omni-directional or directional,and determine a default channel sensing threshold, if the channelsensing threshold is not configured. The default channel sensingthreshold includes two parts: a first part of the default channelsensing threshold being common for omni-directional and directionalantenna configurations and a second part of the default channel sensingthreshold depending on the antenna configuration. The processor isfurther configured to perform a channel sensing procedure based on theantenna configuration and the default channel sensing threshold. The UEfurther includes a transceiver operably connected to the processor. Thetransceiver is configured to transmit DL data over a channel, if thechannel is sensed as idle in the channel sensing procedure.

In yet another embodiment, a method of a UE in a wireless communicationsystem operating with shared spectrum channel access is provided. Themethod includes determining whether a channel sensing threshold isconfigured, determining whether an antenna configuration for channelsensing is omni-directional or directional, and determining a defaultchannel sensing threshold based on determining that the channel sensingthreshold is not configured. The default channel sensing thresholdincludes two parts: a first part of the default channel sensingthreshold being common for omni-directional and directional antennaconfigurations and a second part of the default channel sensingthreshold depending on the antenna configuration. The method furtherincludes performing a channel sensing procedure based on the antennaconfiguration and the default channel sensing threshold and transmittingDL data over a channel based on the channel being sensed as idle in thechannel sensing procedure.

Other technical features may be readily apparent to one skilled in theart from the following figures, descriptions, and claims.

Before undertaking the DETAILED DESCRIPTION below, it may beadvantageous to set forth definitions of certain words and phrases usedthroughout this patent document. The term “couple” and its derivativesrefer to any direct or indirect communication between two or moreelements, whether or not those elements are in physical contact with oneanother. The terms “transmit,” “receive,” and “communicate,” as well asderivatives thereof, encompass both direct and indirect communication.The terms “include” and “comprise,” as well as derivatives thereof, meaninclusion without limitation. The term “or” is inclusive, meaningand/or. The phrase “associated with,” as well as derivatives thereof,means to include, be included within, interconnect with, contain, becontained within, connect to or with, couple to or with, be communicablewith, cooperate with, interleave, juxtapose, be proximate to, be boundto or with, have, have a property of, have a relationship to or with, orthe like. The term “controller” means any device, system, or partthereof that controls at least one operation. Such a controller may beimplemented in hardware or a combination of hardware and software and/orfirmware. The functionality associated with any particular controllermay be centralized or distributed, whether locally or remotely. Thephrase “at least one of,” when used with a list of items, means thatdifferent combinations of one or more of the listed items may be used,and only one item in the list may be needed. For example, “at least oneof: A, B, and C” includes any of the following combinations: A, B, C, Aand B, A and C, B and C, and A and B and C.

Moreover, various functions described below can be implemented orsupported by one or more computer programs, each of which is formed fromcomputer readable program code and embodied in a computer readablemedium. The terms “application” and “program” refer to one or morecomputer programs, software components, sets of instructions,procedures, functions, objects, classes, instances, related data, or aportion thereof adapted for implementation in a suitable computerreadable program code. The phrase “computer readable program code”includes any type of computer code, including source code, object code,and executable code. The phrase “computer readable medium” includes anytype of medium capable of being accessed by a computer, such as readonly memory (ROM), random access memory (RAM), a hard disk drive, acompact disc (CD), a digital video disc (DVD), or any other type ofmemory. A “non-transitory” computer readable medium excludes wired,wireless, optical, or other communication links that transporttransitory electrical or other signals. A non-transitory computerreadable medium includes media where data can be permanently stored andmedia where data can be stored and later overwritten, such as arewritable optical disc or an erasable memory device.

Definitions for other certain words and phrases are provided throughoutthis patent document. Those of ordinary skill in the art shouldunderstand that in many if not most instances, such definitions apply toprior as well as future uses of such defined words and phrases.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present disclosure and itsadvantages, reference is now made to the following description taken inconjunction with the accompanying drawings, in which like referencenumerals represent like parts:

FIG. 1 illustrates an example wireless network according to embodimentsof the present disclosure;

FIG. 2 illustrates an example gNB according to embodiments of thepresent disclosure;

FIG. 3 illustrates an example UE according to embodiments of the presentdisclosure;

FIGS. 4 and 5 illustrate example wireless transmit and receive pathsaccording to this disclosure;

FIG. 6 illustrate an example adaptation of channel sensing thresholdbased on antenna configuration for channel sensing according toembodiments of the present disclosure;

FIG. 7 illustrates an example one transmission burst associated with aplurality of channel sensing thresholds according to embodiments of thepresent disclosure;

FIGS. 8A, 8B, and 8C illustrates a flowchart of a method of a UE foradapting channel sensing threshold according to embodiments of thepresent disclosure;

FIG. 9 illustrates an example channel access procedure according toembodiments of the present disclosure;

FIG. 10 illustrates another example channel access procedure accordingto embodiments of the present disclosure;

FIG. 11 illustrates yet another example channel access procedureaccording to embodiments of the present disclosure;

FIG. 12 illustrates yet another example channel access procedureaccording to embodiments of the present disclosure;

FIG. 13 illustrates an example discontinuity in a transmission burst forchannel access procedure according to embodiments of the presentdisclosure;

FIG. 14 illustrates another example discontinuity in a transmissionburst for channel access procedure according to embodiments of thepresent disclosure; and

FIG. 15 illustrates a flow chart of a method for adapting channelsensing threshold according to embodiments of the present disclosure.

DETAILED DESCRIPTION

FIG. 1 through FIG. 15 , discussed below, and the various embodimentsused to describe the principles of the present disclosure in this patentdocument are by way of illustration only and should not be construed inany way to limit the scope of the disclosure. Those skilled in the artwill understand that the principles of the present disclosure may beimplemented in any suitably arranged system or device.

The following documents are hereby incorporated by reference into thepresent disclosure as if fully set forth herein: 3GPP TS 38.211 v15.7.0,“NR; Physical channels and modulation”; 3GPP TS 38.212 v15.7.0, “NR;Multiplexing and Channel coding”; 3GPP TS 38.213 v15.7.0, “NR; PhysicalLayer Procedures for Control”; 3GPP TS 38.214 v15.7.0, “NR; PhysicalLayer Procedures for Data”; and 3GPP TS 38.331 v15.7.0, “NR; RadioResource Control (RRC) Protocol Specification.”

FIGS. 1-3 below describe various embodiments implemented in wirelesscommunications systems and with the use of orthogonal frequency divisionmultiplexing (OFDM) or orthogonal frequency division multiple access(OFDMA) communication techniques. The descriptions of FIGS. 1-3 are notmeant to imply physical or architectural limitations to the manner inwhich different embodiments may be implemented. Different embodiments ofthe present disclosure may be implemented in any suitably-arrangedcommunications system.

FIG. 1 illustrates an example wireless network according to embodimentsof the present disclosure. The embodiment of the wireless network shownin FIG. 1 is for illustration only. Other embodiments of the wirelessnetwork 100 could be used without departing from the scope of thisdisclosure.

As shown in FIG. 1 , the wireless network includes a gNB 101 (e.g., basestation, BS), a gNB 102, and a gNB 103. The gNB 101 communicates withthe gNB 102 and the gNB 103. The gNB 101 also communicates with at leastone network 130, such as the Internet, a proprietary Internet Protocol(IP) network, or other data network.

The gNB 102 provides wireless broadband access to the network 130 for afirst plurality of user equipments (UEs) within a coverage area 120 ofthe gNB 102. The first plurality of UEs includes a UE 111, which may belocated in a small business; a UE 112, which may be located in anenterprise (E); a UE 113, which may be located in a WiFi hotspot (HS); aUE 114, which may be located in a first residence (R); a UE 115, whichmay be located in a second residence (R); and a UE 116, which may be amobile device (M), such as a cell phone, a wireless laptop, a wirelessPDA, or the like. The gNB 103 provides wireless broadband access to thenetwork 130 for a second plurality of UEs within a coverage area 125 ofthe gNB 103. The second plurality of UEs includes the UE 115 and the UE116. In some embodiments, one or more of the gNBs 101-103 maycommunicate with each other and with the UEs 111-116 using 5G/NR, LTE,LTE-A, WiMAX, WiFi, or other wireless communication techniques.

Depending on the network type, the term “base station” or “BS” can referto any component (or collection of components) configured to providewireless access to a network, such as transmit point (TP),transmit-receive point (TRP), an enhanced base station (eNodeB or eNB),a 5G/NR base station (gNB), a macrocell, a femtocell, a WiFi accesspoint (AP), or other wirelessly enabled devices. Base stations mayprovide wireless access in accordance with one or more wirelesscommunication protocols, e.g., 5G/NR 3GPP NR, long term evolution (LTE),LTE advanced (LTE-A), high speed packet access (HSPA), Wi-Fi802.11a/b/g/n/ac, etc. For the sake of convenience, the terms “BS” and“TRP” are used interchangeably in this patent document to refer tonetwork infrastructure components that provide wireless access to remoteterminals. Also, depending on the network type, the term “userequipment” or “UE” can refer to any component such as “mobile station,”“subscriber station,” “remote terminal,” “wireless terminal,” “receivepoint,” or “user device.” For the sake of convenience, the terms “userequipment” and “UE” are used in this patent document to refer to remotewireless equipment that wirelessly accesses a BS, whether the UE is amobile device (such as a mobile telephone or smartphone) or is normallyconsidered a stationary device (such as a desktop computer or vendingmachine).

Dotted lines show the approximate extents of the coverage areas 120 and125, which are shown as approximately circular for the purposes ofillustration and explanation only. It should be clearly understood thatthe coverage areas associated with gNBs, such as the coverage areas 120and 125, may have other shapes, including irregular shapes, dependingupon the configuration of the gNBs and variations in the radioenvironment associated with natural and man-made obstructions.

As described in more detail below, one or more of the UEs 111-116include circuitry, programing, or a combination thereof, for beammanagement and coverage enhancements for adapting a channel sensingthreshold. In certain embodiments, and one or more of the gNBs 101-103includes circuitry, programing, or a combination thereof, for adapting achannel sensing threshold.

Although FIG. 1 illustrates one example of a wireless network, variouschanges may be made to FIG. 1 . For example, the wireless network couldinclude any number of gNBs and any number of UEs in any suitablearrangement. Also, the gNB 101 could communicate directly with anynumber of UEs and provide those UEs with wireless broadband access tothe network 130. Similarly, each gNB 102-103 could communicate directlywith the network 130 and provide UEs with direct wireless broadbandaccess to the network 130. Further, the gNBs 101, 102, and/or 103 couldprovide access to other or additional external networks, such asexternal telephone networks or other types of data networks.

FIG. 2 illustrates an example gNB 102 according to embodiments of thepresent disclosure. The embodiment of the gNB 102 illustrated in FIG. 2is for illustration only, and the gNBs 101 and 103 of FIG. 1 could havethe same or similar configuration. However, gNBs come in a wide varietyof configurations, and FIG. 2 does not limit the scope of thisdisclosure to any particular implementation of a gNB.

As shown in FIG. 2 , the gNB 102 includes multiple antennas 205 a-205 n,multiple RF transceivers 210 a-210 n, transmit (TX) processing circuitry215, and receive (RX) processing circuitry 220. The gNB 102 alsoincludes a controller/processor 225, a memory 230, and a backhaul ornetwork interface 235.

The RF transceivers 210 a-210 n receive, from the antennas 205 a-205 n,incoming RF signals, such as signals transmitted by UEs in the network100. The RF transceivers 210 a-210 n down-convert the incoming RFsignals to generate IF or baseband signals. The IF or baseband signalsare sent to the RX processing circuitry 220, which generates processedbaseband signals by filtering, decoding, and/or digitizing the basebandor IF signals. The RX processing circuitry 220 transmits the processedbaseband signals to the controller/processor 225 for further processing.

The TX processing circuitry 215 receives analog or digital data (such asvoice data, web data, e-mail, or interactive video game data) from thecontroller/processor 225. The TX processing circuitry 215 encodes,multiplexes, and/or digitizes the outgoing baseband data to generateprocessed baseband or IF signals. The RF transceivers 210 a-210 nreceive the outgoing processed baseband or IF signals from the TXprocessing circuitry 215 and up-converts the baseband or IF signals toRF signals that are transmitted via the antennas 205 a-205 n.

The controller/processor 225 can include one or more processors or otherprocessing devices that control the overall operation of the gNB 102.For example, the controller/processor 225 could control the reception offorward channel signals and the transmission of reverse channel signalsby the RF transceivers 210 a-210 n, the RX processing circuitry 220, andthe TX processing circuitry 215 in accordance with well-knownprinciples. The controller/processor 225 could support additionalfunctions as well, such as more advanced wireless communicationfunctions. For instance, the controller/processor 225 could support beamforming or directional routing operations in which outgoing/incomingsignals from/to multiple antennas 205 a-205 n are weighted differentlyto effectively steer the outgoing signals in a desired direction. Any ofa wide variety of other functions could be supported in the gNB 102 bythe controller/processor 225.

The controller/processor 225 is also capable of executing programs andother processes resident in the memory 230, such as an OS. Thecontroller/processor 225 can move data into or out of the memory 230 asrequired by an executing process.

The controller/processor 225 is also coupled to the backhaul or networkinterface 235. The backhaul or network interface 235 allows the gNB 102to communicate with other devices or systems over a backhaul connectionor over a network. The interface 235 could support communications overany suitable wired or wireless connection(s). For example, when the gNB102 is implemented as part of a cellular communication system (such asone supporting 5G/NR, LTE, or LTE-A), the interface 235 could allow thegNB 102 to communicate with other gNBs over a wired or wireless backhaulconnection. When the gNB 102 is implemented as an access point, theinterface 235 could allow the gNB 102 to communicate over a wired orwireless local area network or over a wired or wireless connection to alarger network (such as the Internet). The interface 235 includes anysuitable structure supporting communications over a wired or wirelessconnection, such as an Ethernet or RF transceiver.

The memory 230 is coupled to the controller/processor 225. Part of thememory 230 could include a RAM, and another part of the memory 230 couldinclude a Flash memory or other ROM.

Although FIG. 2 illustrates one example of gNB 102, various changes maybe made to FIG. 2 . For example, the gNB 102 could include any number ofeach component shown in FIG. 2 . As a particular example, an accesspoint could include a number of interfaces 235, and thecontroller/processor 225 could support routing functions to route databetween different network addresses. As another particular example,while shown as including a single instance of TX processing circuitry215 and a single instance of RX processing circuitry 220, the gNB 102could include multiple instances of each (such as one per RFtransceiver). Also, various components in FIG. 2 could be combined,further subdivided, or omitted and additional components could be addedaccording to particular needs.

FIG. 3 illustrates an example UE 116 according to embodiments of thepresent disclosure. The embodiment of the UE 116 illustrated in FIG. 3is for illustration only, and the UEs 111-115 of FIG. 1 could have thesame or similar configuration. However, UEs come in a wide variety ofconfigurations, and FIG. 3 does not limit the scope of this disclosureto any particular implementation of a UE.

As shown in FIG. 3 , the UE 116 includes an antenna 305, a radiofrequency (RF) transceiver 310, TX processing circuitry 315, amicrophone 320, and receive (RX) processing circuitry 325. The UE 116also includes a speaker 330, a processor 340, an input/output (I/O)interface (IF) 345, a touchscreen 350, a display 355, and a memory 360.The memory 360 includes an operating system (OS) 361 and one or moreapplications 362.

The RF transceiver 310 receives, from the antenna 305, an incoming RFsignal transmitted by a gNB of the network 100. The RF transceiver 310down-converts the incoming RF signal to generate an intermediatefrequency (IF) or baseband signal. The IF or baseband signal is sent tothe RX processing circuitry 325, which generates a processed basebandsignal by filtering, decoding, and/or digitizing the baseband or IFsignal. The RX processing circuitry 325 transmits the processed basebandsignal to the speaker 330 (such as for voice data) or to the processor340 for further processing (such as for web browsing data).

The TX processing circuitry 315 receives analog or digital voice datafrom the microphone 320 or other outgoing baseband data (such as webdata, e-mail, or interactive video game data) from the processor 340.The TX processing circuitry 315 encodes, multiplexes, and/or digitizesthe outgoing baseband data to generate a processed baseband or IFsignal. The RF transceiver 310 receives the outgoing processed basebandor IF signal from the TX processing circuitry 315 and up-converts thebaseband or IF signal to an RF signal that is transmitted via theantenna 305.

The processor 340 can include one or more processors or other processingdevices and execute the OS 361 stored in the memory 360 in order tocontrol the overall operation of the UE 116. For example, the processor340 could control the reception of forward channel signals and thetransmission of reverse channel signals by the RF transceiver 310, theRX processing circuitry 325, and the TX processing circuitry 315 inaccordance with well-known principles. In some embodiments, theprocessor 340 includes at least one microprocessor or microcontroller.

The processor 340 is also capable of executing other processes andprograms resident in the memory 360, such as processes for beammanagement. The processor 340 can move data into or out of the memory360 as required by an executing process. In some embodiments, theprocessor 340 is configured to execute the applications 362 based on theOS 361 or in response to signals received from gNBs or an operator. Theprocessor 340 is also coupled to the I/O interface 345, which providesthe UE 116 with the ability to connect to other devices, such as laptopcomputers and handheld computers. The I/O interface 345 is thecommunication path between these accessories and the processor 340.

The processor 340 is also coupled to the touchscreen 350 and the display355. The operator of the UE 116 can use the touchscreen 350 to enterdata into the UE 116. The display 355 may be a liquid crystal display,light emitting diode display, or other display capable of rendering textand/or at least limited graphics, such as from web sites.

The memory 360 is coupled to the processor 340. Part of the memory 360could include a random access memory (RAM), and another part of thememory 360 could include a Flash memory or other read-only memory (ROM).

Although FIG. 3 illustrates one example of UE 116, various changes maybe made to FIG. 3 . For example, various components in FIG. 3 could becombined, further subdivided, or omitted and additional components couldbe added according to particular needs. As a particular example, theprocessor 340 could be divided into multiple processors, such as one ormore central processing units (CPUs) and one or more graphics processingunits (GPUs). Also, while FIG. 3 illustrates the UE 116 configured as amobile telephone or smartphone, UEs could be configured to operate asother types of mobile or stationary devices.

To meet the demand for wireless data traffic having increased sincedeployment of 4G communication systems and to enable various verticalapplications, efforts have been made to develop and deploy an improved5G/NR or pre-5G/NR communication system. Therefore, the 5G/NR orpre-5G/NR communication system is also called a “beyond 4G network” or a“post LTE system.” The 5G/NR communication system is considered to beimplemented in higher frequency (mmWave) bands, e.g., 28 GHz or 60 GHzbands, so as to accomplish higher data rates or in lower frequencybands, such as 6 GHz, to enable robust coverage and mobility support.The present disclosure may also be applied to deployment of 5Gcommunication system, 6G or even later release which may use terahertz(THz) bands. To decrease propagation loss of the radio waves andincrease the transmission distance, the beamforming, massivemultiple-input multiple-output (MIMO), full dimensional MIMO (FD-MIMO),array antenna, an analog beam forming, large scale antenna techniquesare discussed in 5G/NR communication systems.

In addition, in 5G/NR communication systems, development for systemnetwork improvement is under way based on advanced small cells, cloudradio access networks (RANs), ultra-dense networks, device-to-device(D2D) communication, wireless backhaul, moving network, cooperativecommunication, coordinated multi-points (CoMP), reception-endinterference cancellation and the like.

A communication system includes a downlink (DL) that refers totransmissions from a base station or one or more transmission points toUEs and an uplink (UL) that refers to transmissions from UEs to a basestation or to one or more reception points.

A time unit for DL signaling or for UL signaling on a cell is referredto as a slot and can include one or more symbols. A symbol can alsoserve as an additional time unit. A frequency (or bandwidth (BW)) unitis referred to as a resource block (RB). One RB includes a number ofsub-carriers (SCs). For example, a slot can have duration of 0.5milliseconds or 1 millisecond, include 14 symbols and an RB can include12 SCs with inter-SC spacing of 15 KHz or 30 KHz, and so on.

DL signals include data signals conveying information content, controlsignals conveying DL control information (DCI), and reference signals(RS) that are also known as pilot signals. A gNB transmits datainformation or DCI through respective physical DL shared channels(PDSCHs) or physical DL control channels (PDCCHs). A PDSCH or a PDCCHcan be transmitted over a variable number of slot symbols including oneslot symbol. For brevity, a DCI format scheduling a PDSCH reception by aUE is referred to as a DL DCI format and a DCI format scheduling aphysical uplink shared channel (PUSCH) transmission from a UE isreferred to as an UL DCI format.

A gNB transmits one or more of multiple types of RS including channelstate information RS (CSI-RS) and demodulation RS (DMRS). A CSI-RS isprimarily intended for UEs to perform measurements and provide CSI to agNB. For channel measurement, non-zero power CSI-RS (NZP CSI-RS)resources are used. For interference measurement reports (IMRs), CSIinterference measurement (CSI-IM) resources associated with a zero powerCSI-RS (ZP CSI-RS) configuration are used. A CSI process includes NZPCSI-RS and CSI-IM resources.

A UE can determine CSI-RS transmission parameters through DL controlsignaling or higher layer signaling, such as radio resource control(RRC) signaling, from a gNB. Transmission instances of a CSI-RS can beindicated by DL control signaling or be configured by higher layersignaling. A DMRS is transmitted only in the BW of a respective PDCCH orPDSCH and a UE can use the DMRS to demodulate data or controlinformation.

FIG. 4 and FIG. 5 illustrate example wireless transmit and receive pathsaccording to this disclosure. In the following description, a transmitpath 400 may be described as being implemented in a gNB (such as the gNB102), while a receive path 500 may be described as being implemented ina UE (such as a UE 116). However, it may be understood that the receivepath 500 can be implemented in a gNB and that the transmit path 400 canbe implemented in a UE. In some embodiments, the receive path 500 isconfigured to support adapting a channel sensing threshold as describedin embodiments of the present disclosure.

The transmit path 400 as illustrated in FIG. 4 includes a channel codingand modulation block 405, a serial-to-parallel (S-to-P) block 410, asize N inverse fast Fourier transform (IFFT) block 415, aparallel-to-serial (P-to-S) block 420, an add cyclic prefix block 425,and an up-converter (UC) 430. The receive path 500 as illustrated inFIG. 5 includes a down-converter (DC) 555, a remove cyclic prefix block560, a serial-to-parallel (S-to-P) block 565, a size N fast Fouriertransform (FFT) block 570, a parallel-to-serial (P-to-S) block 575, anda channel decoding and demodulation block 580.

As illustrated in FIG. 400 , the channel coding and modulation block 405receives a set of information bits, applies coding (such as alow-density parity check (LDPC) coding), and modulates the input bits(such as with quadrature phase shift keying (QPSK) or quadratureamplitude modulation (QAM)) to generate a sequence of frequency-domainmodulation symbols.

The serial-to-parallel block 410 converts (such as de-multiplexes) theserial modulated symbols to parallel data in order to generate Nparallel symbol streams, where N is the IFFT/FFT size used in the gNB102 and the UE 116. The size N IFFT block 415 performs an IFFT operationon the N parallel symbol streams to generate time-domain output signals.The parallel-to-serial block 420 converts (such as multiplexes) theparallel time-domain output symbols from the size N IFFT block 415 inorder to generate a serial time-domain signal. The add cyclic prefixblock 425 inserts a cyclic prefix to the time-domain signal. Theup-converter 430 modulates (such as up-converts) the output of the addcyclic prefix block 425 to an RF frequency for transmission via awireless channel. The signal may also be filtered at baseband beforeconversion to the RF frequency.

A transmitted RF signal from the gNB 102 arrives at the UE 116 afterpassing through the wireless channel, and reverse operations to those atthe gNB 102 are performed at the UE 116.

As illustrated in FIG. 5 , the down-converter 555 down-converts thereceived signal to a baseband frequency, and the remove cyclic prefixblock 560 removes the cyclic prefix to generate a serial time-domainbaseband signal. The serial-to-parallel block 565 converts thetime-domain baseband signal to parallel time domain signals. The size NFFT block 570 performs an FFT algorithm to generate N parallelfrequency-domain signals. The parallel-to-serial block 575 converts theparallel frequency-domain signals to a sequence of modulated datasymbols. The channel decoding and demodulation block 580 demodulates anddecodes the modulated symbols to recover the original input data stream.

Each of the gNBs 101-103 may implement a transmit path 400 asillustrated in FIG. 4 that is analogous to transmitting in the downlinkto UEs 111-116 and may implement a receive path 500 as illustrated inFIG. 5 that is analogous to receiving in the uplink from UEs 111-116.Similarly, each of UEs 111-116 may implement the transmit path 400 fortransmitting in the uplink to the gNBs 101-103 and may implement thereceive path 500 for receiving in the downlink from the gNBs 101-103.

Each of the components in FIG. 4 and FIG. 5 can be implemented usingonly hardware or using a combination of hardware and software/firmware.As a particular example, at least some of the components in FIG. 4 andFIG. 5 may be implemented in software, while other components may beimplemented by configurable hardware or a mixture of software andconfigurable hardware. For instance, the FFT block 570 and the IFFTblock 515 may be implemented as configurable software algorithms, wherethe value of size N may be modified according to the implementation.

Furthermore, although described as using FFT and IFFT, this is by way ofillustration only and may not be construed to limit the scope of thisdisclosure. Other types of transforms, such as discrete Fouriertransform (DFT) and inverse discrete Fourier transform (IDFT) functions,can be used. It may be appreciated that the value of the variable N maybe any integer number (such as 1, 2, 3, 4, or the like) for DFT and IDFTfunctions, while the value of the variable N may be any integer numberthat is a power of two (such as 1, 2, 4, 8, 16, or the like) for FFT andIFFT functions.

Although FIG. 4 and FIG. 5 illustrate examples of wireless transmit andreceive paths, various changes may be made to FIG. 4 and FIG. 5 . Forexample, various components in FIG. 4 and FIG. 5 can be combined,further subdivided, or omitted and additional components can be addedaccording to particular needs. Also, FIG. 4 and FIG. 5 are meant toillustrate examples of the types of transmit and receive paths that canbe used in a wireless network. Any other suitable architectures can beused to support wireless communications in a wireless network.

This disclosure focuses on adaptation of channel sensing threshold basedon the antenna configuration for sensing the channel. The channelsensing threshold can be associated with the intended transmissiondirection and be indicated to the UE by a higher layer parameter or aPHY layer parameter. More precisely, the following components areprovided in this disclosure: a directional channel sensing threshold;channel sensing threshold association; a channel sensing thresholddetermination; and/or a UE procedure for a utilizing channel sensingthreshold.

For operation with a shared spectrum channel access (e.g., unlicensed orshared spectrum), a transmitter may perform sensing that evaluates theavailability of a channel for performing transmissions. For energydetection based sensing, a basic unit for sensing is defined as asensing slot. A channel with a duration of s sensing slot is declared asidle, if the transmitter senses the channel during the sensing slotduration and determines that the detected power for a given portion ofthe sensing slot duration is less than a sensing threshold X_(Thresh),or declared as busy otherwise.

In NR Rel-16, an operation with shared spectrum channel access has beensupported for 5 GHz unlicensed band and 6 GHz unlicensed band. Moreprecisely, for 5 GHz unlicensed band and 6 GHz unlicensed band, thesensing slot is defined as T_(s1)=9 us, and the sensing threshold can beadapted according to a maximum energy detection threshold.

In a DL, a gNB accessing a channel on which transmission(s) areperformed, may set the energy detection threshold (X_(Thresh)) to beless than or equal to the maximum energy detection thresholdX_(Thresh_max), wherein X_(Thresh_max) is determined as shown in TABLE1.

TABLE 1 Energy detection threshold determination - If the absence of anyother technology sharing the channel can be guaranteed on a long-termbasis (e.g., by level of regulation) then:$‐{X_{{Thresh}\_\max} = {\min\begin{Bmatrix}{{T_{\max} + {10{dB}}},} \\X_{r}\end{Bmatrix}}}$ - X_(r) is Maximum energy detection threshold definedby regulatory requirements in dBm when such requirements are defined,otherwise X_(r) = T_(max) + 10 dB - Otherwise,$‐{X_{Thresh\_ max} = {\max\begin{Bmatrix}{{{- 72} + {{10 \cdot \log}10\left( {{BWMHz}/20{MHz}} \right){dBm}}},} \\{\min\begin{Bmatrix}{T_{\max},} \\{T_{\max} - T_{A} + \left( {P_{H} + {10 \cdot}} \right.} \\\left. {{\log 10\left( {{BWMHz}/20{MHz}} \right)} - P_{TX}} \right)\end{Bmatrix}}\end{Bmatrix}}}$ - Where: - T_(A) = 10 dB for transmission(s) includingPDSCH; - T_(A) = 5 dB for transmissions including discovery burst(s); -P_(H) = 23 dBm; - P_(TX) is the set maximum eNB/gNB output power in dBmfor the channel; - eNB/gNB uses the set maximum transmission power overa single channel irrespective of whether single channel or multi-channeltransmission is employed - T_(max) (dBm) = 10 · log 10 (3.16228 · 10⁻⁸(mW/MHz) · BWMHz (MHz)); - BWMHz is the single channel bandwidth in MHz.

In an UL, a UE accessing a channel on which UL transmission(s) areperformed, may set the energy detection threshold (X_(Thresh)) to beless than or equal to the maximum energy detection thresholdX_(Thresh_max), wherein X_(Thresh_max) is determined as shown in TABLE2.

TABLE 2 Energy detection threshold determination - If the UE isconfigured with higher layer parameter maxEnergyDetectionThreshold-r14or maxEnergyDetectionThreshold-r16,  - X_(Thresh) _(—) _(max) is setequal to the value signaled by the higher layer parameter. - otherwise - the UE may determine X′_(Thresh) _(—) _(max) as follow.  - if the UEis configured with higher layer parameterenergyDetectionThresholdOffset-r14 or energyDetectionThresholdOffset-r16 - X_(Thresh) _(—) _(max) is set by adjusting X′_(Thresh) _(—) _(max)according to the offset value signaled by the higher layer parameter -otherwise  - The UE may set X_(Thresh) _(—) _(max) = X′_(Thresh) _(—)_(max)

If the higher layer parameter absenceOfAnyOtherTechnology-r16 is notconfigured to a UE, and the higher layer parameterULtoDL-CO-SharingED-Threshold-r16 is configured to the UE, the gNB mayuse the gNB's transmit power in determining the resulting energydetection threshold ULtoDL-CO-SharingED-Threshold-r16.

For the case where a UE performs channel access procedures and sharesthe corresponding channel occupancy time with the gNB, X_(Thresh_max) isset equal to the value provided by the higher layer parameterULtoDL-CO-SharingED-Threshold-r16, if provided.

If the higher layer parameter absenceOfAnyOtherTechnology-r14 orabsenceOfAnyOtherTechnology-r16, parameters are provided as shown inTABLE 3.

TABLE 3 Parameters $‐{X_{{Thresh}\_\max}^{\prime} = {\min\begin{Bmatrix}{T_{\max} + {10{dB}}} \\X_{r}\end{Bmatrix}{where}}}$ - X_(r) is Maximum energy detection thresholddefined by regulatory requirements in dBm when such requirements aredefined, otherwise X_(r) = T_(max) + 10 dB otherwise$‐{X_{Thresh\_ max}^{\prime} = {\max\begin{Bmatrix}{{{- 72} + {{10 \cdot \log}10\left( {{BWMHz}/20{MHz}} \right){dBm}}},} \\{\min\begin{Bmatrix}{T_{\max},} \\{T_{\max} - T_{A} + \left( {P_{H} + {10 \cdot}} \right.} \\\left. {{\log 10\left( {{BWMHz}/20{MHz}} \right)} - P_{TX}} \right)\end{Bmatrix}}\end{Bmatrix}}}$ Where - T_(A) = 10 dB - P_(H) = 23 dBm; - P_(TX) is theset to the value of P_(CMAX)_H,c. - T_(max) (dBm) = 10 · log 10 (3.16228· 10⁻⁸ (mW/MHz) · BWMHz (MHz)) ; - BWMHz is the single channel bandwidthin MHz.

For higher carrier frequency range, for example 60 GHz unlicensedspectrum, transmissions may utilize highly-directional beamforming. Tosupport this, the corresponding channel sensing could also be configuredto be highly-directional, in order to save sensing energy on directionsnot related to the intended transmission, wherein the new type ofsensing is referred to as directional channel sensing, to bedistinguished from classical omni-directional channel sensing. Thisdisclosure specifies the adaptation on the channel sensing threshold.

Although exemplary descriptions and embodiments to follow assume OFDM orOFDMA, this disclosure can be extended to other OFDM-based transmissionwaveforms or multiple access schemes such as filtered OFDM (F-OFDM).

This disclosure covers several components which can be used inconjunction or in combination with one another or can operate asstandalone schemes.

In one embodiment, a channel sensing threshold can be adapted based onthe antenna configuration for channel sensing.

In one example, whether the channel sensing threshold is adapted basedon the antenna configuration for channel sensing can be indicated in thesystem information.

In one example, whether the channel sensing threshold is adapted basedon the antenna configuration for channel sensing can be configured by aRRC parameter.

In one example, there can be a channel sensing threshold offset appliedto a common channel sensing threshold regardless of the antennaconfiguration (e.g. the maximum channel sensing thresholdX_(Thresh_max)), wherein the channel sensing threshold offset can bedenoted as X_(Thresh_offset), and the channel sensing threshold offsetis based on the antenna configuration for channel sensing.

FIG. 6 illustrate an example adaptation of channel sensing threshold 600based on antenna configuration for channel sensing according toembodiments of the present disclosure. An embodiment of the adaptationof channel sensing threshold 600 shown in FIG. 6 is for illustrationonly.

In one example, the channel sensing threshold offset can be applicableto directional channel sensing, wherein the antenna configuration forchannel sensing is directional, e.g. X_(Thresh_offset)>0, if the antennaconfiguration for channel sensing is directional.

In one example, the channel sensing threshold offset can be determinedas X_(Thresh_offset)=0, if the antenna configuration for channel sensingis omni-directional.

In one example, whether the channel sensing threshold offset isapplicable can be based on the configuration that whether the channelsensing threshold is adapted based on the antenna configuration forchannel sensing.

In one example, the maximum channel sensing threshold X_(Thresh_max) canbe based on the antenna configuration for channel sensing. Theseexamples are illustrated in 601 and 602 of FIG. 6 .

In one example, the channel sensing threshold can be different for theantenna configuration for channel sensing being directional oromni-directional.

In one example, if the configuration indicates that the channel sensingthreshold is adapted based on the antenna configuration for channelsensing, the channel sensing threshold can be different for the antennaconfiguration for channel sensing being directional or omni-directional;otherwise, the channel sensing threshold maintains the same.

In one example, the adaptation of the channel sensing threshold can bebased on a number of antenna configurations (e.g., number ofdirections/beams). In this example, the channel sensing threshold forall the antenna configurations (e.g., directions/beams) are the same,e.g., a common X_(Thresh_max) or X_(Thresh_offset) based on the numberof antenna configurations (e.g., number of directions/beams). Forinstance, X_(Thresh_offset)=f(N_(beam)) or X_(Thresh_max)=f(N_(beam)),where N_(beam) is the number of antenna configurations (e.g., number ofdirections/beams).

In another example, the adaptation of the channel sensing threshold canbe based on one or a group of antenna configurations. In this example,the channel sensing threshold can be direction-specific orgroup-of-direction-specific, e.g., X_(Thresh_max) or X_(Thresh_offset)is based on a direction or a group of directions. For instance,X_(Thresh_max)(i_(beam))=f(i_(beam)), orX_(Thresh_offset)(i_(beam))=f(i_(beam)), wherein i_(beam) is the indexof a direction or a group of directions.

In one embodiment, there is an association between the channel sensingthreshold and an antenna configuration.

In one example, there can be an association between an antenna port anda channel sensing threshold. In one example, when transmitting signal(s)and/or channel(s) using the antenna port, the associated channel censingthreshold may be utilized.

In one example, a gNB can configure a channel sensing threshold and/or achannel sensing threshold offset to be associated with an antenna port.In one example, the configuration can be indicated in the systeminformation. In one example, the configuration can be indicated in adedicated RRC parameter.

In one example, the association between an antenna port and a channelsensing threshold and/or a channel sensing threshold offset can be hardcoded and fixed in the specification.

In one example, there can be an association between a reference signaland a channel sensing threshold.

In one example, at least signals in a synchronization signal/physicalbroadcasting channel (SS/PBCH) block can be the reference signal to beassociated with a channel sensing threshold. In one example, a gNB canconfigure a channel sensing threshold and/or a channel sensing thresholdoffset to be associated with an index of SS/PBCH block. In one example,the association can be indicated in a RRC parameter. In another example,the association can be indicated in a DCI format. For one instance ofthis example, RRC parameter can configure a set of possible values forthe channel sensing threshold and/or channel sensing threshold offset,and the DCI format indicates the association between the index ofSS/PBCH block and the value of channel sensing threshold and/or channelsensing threshold offset.

In another example of a reference signal, at least a CSI-RS can be thereference signal to be associated with a channel sensing threshold. Inone example, a gNB can configure a channel sensing threshold and/or achannel sensing threshold offset to be associated with an index ofCSI-RS resource. In one example, the association can be indicated in aRRC parameter. In another example, the association can be indicated in aDCI format. For one instance of this example, RRC parameter canconfigure a set of possible values for the channel sensing thresholdand/or channel sensing threshold offset, and the DCI format indicatesthe association between the index of CSI-RS resource and the value ofchannel sensing threshold and/or channel sensing threshold offset.

In yet another example of the reference signal, at least an SRS can bethe reference signal to be associated with a channel sensing threshold.In one example, a gNB can configure a channel sensing threshold and/or achannel sensing threshold offset to be associated with an index of SRSresource.

In one example, there can be an association between a quasi co-location(QCL) assumption and a channel sensing threshold.

In one example, signals with the same QCL assumption can be associatedwith the same channel sensing threshold.

In one example, there can be an association between a transmissionconfiguration indication state (TCI-state) and a channel sensingthreshold.

For one example, a gNB can configure a channel sensing threshold and/ora channel sensing threshold offset to be associated with a TCI-state. Inone example, the association can be indicated in a RRC parameter. In oneexample, the association can be indicated in a DCI format. For example,RRC parameter can configure a set of possible values for the channelsensing threshold and/or channel sensing threshold offset, and the DCIformat indicates the association between the TCI-state and the value ofchannel sensing threshold and/or channel sensing threshold offset.

In one example, there can be an association between a spatial filter forphysical uplink control channel (PUCCH) (e.g.,PUCCH-SpatialRelationInfo) and a channel sensing threshold.

In one example, a gNB can configure a channel sensing threshold and/or achannel sensing threshold offset to be associated with a spatial filterfor PUCCH (e.g., PUCCH-SpatialRelationInfo). In one instance, theassociation can be indicated in a RRC parameter.

In one example, there can be an association between an indication of adirection/beam or a group of directions/beams and a channel sensingthreshold.

In one example, the indication of a direction/beam can be a bit in abitmap, wherein the bitmap indicates all the directions/beams fortransmission or channel sensing. In one sub-example, the bitmap can be abitmap for a burst of SS/PBCH blocks within a period.

In one embodiment, a transmission burst can include signal(s) and/orchannel(s) being associated with at least one channel sensing threshold,wherein the association can be according to examples in this disclosure.

In one example, if signal(s) and/or channel(s) in a transmission burstare associated with only one channel sensing threshold, then thetransmitter (e.g., a gNB or a UE) may perform channel sensing accordingto the associated channel sensing threshold.

In one example, signal(s) and/or channel(s) in one transmission burstcan be associated with a plurality of channel sensing thresholds. Anillustration of this example is shown in FIG. 7 , wherein a first partof the transmission burst is associated with a first channel sensingthreshold, and a second part of the transmission burst is associatedwith a second part of sensing threshold.

FIG. 7 illustrates an example one transmission burst associated with aplurality of channel sensing thresholds 700 according to embodiments ofthe present disclosure. An embodiment of the one transmission burstassociated with a plurality of channel sensing thresholds 700 shown inFIG. 7 is for illustration only.

In one example, the channel sensing threshold applied to initialize thetransmission burst may be no larger than the minimum of all theassociated channel sensing thresholds.

In one example, the channel sensing threshold applied to initialize thetransmission burst may be no larger than the maximum of all theassociated channel sensing thresholds.

In one example, the channel sensing threshold applied to initialize thetransmission burst may be no larger than the average of all theassociated channel sensing thresholds.

In one embodiment, a UE can be configured a channel sensing threshold ora channel sensing threshold offset, wherein the channel sensingthreshold or the channel sensing threshold offset can be adapted basedon antenna configuration for a UE's transmission.

In one embodiment, if the UE is not provided a channel sensing thresholdor a channel sensing threshold offset by the higher layer, the UE usesthe default channel sensing threshold to perform channel sensing,wherein the default channel sensing threshold does not include theimpact from directional antenna configuration for the UE's transmission(e.g., assuming omni-directional antenna configuration).

In another embodiment, if the UE is provided a channel sensing thresholdor a channel sensing threshold offset by the higher layer, but theprovided channel sensing threshold or channel sensing threshold offsetis not associated with the directional antenna configuration for theUE's transmission, the UE uses the default channel sensing threshold toperform channel sensing, wherein the default channel sensing thresholddoes not include the impact from directional antenna configuration forthe UE's transmission (e.g., assuming omni-directional antennaconfiguration).

In yet another embodiment, if the UE is provided a channel sensingthreshold, wherein the channel sensing threshold is associated with thedirectional antenna configuration for the UE's transmission, the UE usesthe provided channel sensing threshold to perform channel sensing.

In yet another embodiment, if the UE is provided a channel sensingthreshold offset, wherein the channel sensing threshold offset isassociated with the directional antenna configuration for the UE'stransmission, the UE applies the provided channel sensing thresholdoffset to the default channel sensing threshold and to calculate a newchannel sensing threshold and uses the new channel sensing threshold toperform channel sensing.

FIG. 8A illustrates a flowchart of a method 800 of a UE for adaptingchannel sensing threshold according to embodiments of the presentdisclosure as may be performed by a UE, such as UE 116 in FIG. 1 . Anembodiment of the method 800 shown in FIG. 8A is for illustration only.An embodiment of the method 800 shown in FIG. 8A is for illustrationonly. One or more of the components illustrated in FIG. 8A can beimplemented in specialized circuitry configured to perform the notedfunctions or one or more of the components can be implemented by one ormore processors executing instructions to perform the noted functions.

FIG. 8B illustrates another flowchart of a method 850 of a UE foradapting channel sensing threshold according to embodiments of thepresent disclosure as may be performed by a UE, such as UE 116 in FIG. 1. An embodiment of the method 850 shown in FIG. 8B is for illustrationonly. An embodiment of the method 850 shown in FIG. 8B is forillustration only. One or more of the components illustrated in FIG. 8Bcan be implemented in specialized circuitry configured to perform thenoted functions or one or more of the components can be implemented byone or more processors executing instructions to perform the notedfunctions.

FIG. 8C illustrates yet another flowchart of a method 870 of a UE foradapting channel sensing threshold according to embodiments of thepresent disclosure as may be performed by a UE, such as UE 116 in FIG. 1. An embodiment of the method 870 shown in FIG. 8C is for illustrationonly. An embodiment of the method 870 shown in FIG. 8C is forillustration only. One or more of the components illustrated in FIG. 8Ccan be implemented in specialized circuitry configured to perform thenoted functions or one or more of the components can be implemented byone or more processors executing instructions to perform the notedfunctions.

Example UE procedures for an adapting channel sensing threshold areshown in FIGS. 8A, 8B, and 8C.

This disclosure focuses on the channel access procedure usingdirectional channel sensing, wherein a case of channel access procedurecan be applicable based on the composition of the transmission burst.Examples/embodiments to deal with the potential discontinuity oftransmission burst are also covered by this disclosure. More precisely,the following components are included in this disclosure: channel accessprocedure based on directional sensing; channel access procedure basedon composition of transmission burst; transmission discontinuity in aCase-3B channel access procedure; and/or transmission discontinuity in aCase-4B channel access procedure.

In NR Rel-16, an operation with shared spectrum channel access has beensupported for 5 GHz unlicensed band and 6 GHz unlicensed band. Moreprecisely, two types of channel access procedures are supported, whereinType 1 channel access procedure includes a random time duration ofchannel sensing before a downlink transmission, and Type 2 channelaccess procedure includes a deterministic time duration (e.g., includingzero duration) of channel sensing before a downlink transmission.

In one embodiment, at least one of the following cases of channel accessprocedures can be supported for transmitting a transmission burst withat least one transmission directions.

In one example of Case-1, the antenna for channel sensing before atransmission burst can be configured to be omni-directional orquasi-omni-directional, and one transmission burst follows a channelsensing duration using the omni-directional or quasi-omni-directionalantenna.

In one example, the channel sensing duration can be either random (Type1 channel sensing procedure) or deterministic (Type 2 channel sensingprocedure). Note that Type 2 channel sensing procedure includes a zerosensing duration procedure, which implies transmission can start withoutchannel sensing. In another example, the transmission direction for atransport block included in the transmission burst can be any direction,and there can be one or multiple transmission directions associated withtransport block(s) included in the transmission burst, as shown in 901or 902 of FIG. 9 , respectively.

FIG. 9 illustrates an example channel access procedure 900 according toembodiments of the present disclosure. An embodiment of the channelaccess procedure 900 shown in FIG. 9 is for illustration only.

In one example of Case-2, the antenna for channel sensing before atransmission burst can be configured to be directional for a certaindirection, and one transmission burst follows a channel sensing durationusing the directional antenna. In one example, the channel sensingduration can be either random (Type 1 channel sensing procedure) ordeterministic (Type 2 channel sensing procedure). Note that Type 2channel sensing procedure includes a zero sensing duration procedure,which implies transmission can start without channel sensing. In anotherexample, the direction for channel sensing may be aligned with thedirection for transmission. For example, the antenna filterconfiguration for channel sensing is identical to the antenna filterconfiguration for transmission. An illustration of this case is shown inFIG. 10 .

FIG. 10 illustrates another example channel access procedure 1000according to embodiments of the present disclosure. An embodiment of thechannel access procedure 1000 shown in FIG. 10 is for illustration only.

In one example of Case-3, the antenna for channel sensing before atransmission burst can be configured to be directional for a set ofdirections, and one transmission burst follows a channel sensingduration using the directional antenna for the set of directions. In oneexample, the channel sensing duration can be either random (Type 1channel sensing procedure) or deterministic (Type 2 channel sensingprocedure). Note that Type 2 channel sensing procedure refers to a zerosensing duration procedure, which implies transmission can start withoutchannel sensing; or a positive value sensing duration procedure, whichimplies transmission can start after sensing a fixed time duration ofthe channel to be idle. In another example, the directions for channelsensing may be aligned with the directions for transmission. Forexample, the antenna filter configurations for channel sensing areidentical to the antenna filter configurations for transmission. Anillustration of this case is shown in FIG. 11 . For another example, theantenna filter configurations for channel sensing are a super set of theantenna filter configurations for transmission.

FIG. 11 illustrates yet another example channel access procedure 1100according to embodiments of the present disclosure. An embodiment of thechannel access procedure 1100 shown in FIG. 11 is for illustration only.

In one example of Case-3A, the transmission burst can start regardlessof the sensing result from channel sensing. An example with twodirections is shown in TABLE 4.

In one example of Case-3B, the transmission burst can start but onlyaccording to the direction sensed as idle. An example with twodirections is shown in TABLE 4.

In one example of Case-3C, the transmission burst cannot start if any ofthe sensing direction is busy, which is equivalent as all sensingdirections are idle. An example with two directions is shown in TABLE 4.

TABLE 4 Channel access procedure for the third case. Sensing resultCase-3A Case-3B Case-3C 1st direction idle, Transmit on Transmit onTransmit on 2nd direction idle 1st and/or 1st and/or 1st and/or 2nddirection 2nd direction 2nd direction 1st direction idle, Transmit onTransmit on Cannot 2nd direction busy 1st and/or 1st direction transmit2nd direction 1st direction busy, Transmit on Transmit on Cannot 2nddirection idle 1st and/or 2nd direction transmit 2nd direction 1stdirection busy, Transmit on Cannot Cannot 2nd direction busy 1st and/ortransmit transmit 2nd direction

In one example of Case-4, the antenna for channel sensing before atransmission burst can be configured to be directional for a set ofdirections, and one transmission burst follows a channel sensingduration using the directional antenna for the set of directions.Meanwhile, within the transmission burst, before the transmission of adirection, another channel sensing with antenna configured for thatdirection is performed.

In one example, the channel sensing duration before the transmissionburst can be random (Type 1 channel sensing procedure). In one example,the channel sensing duration within the transmission burst can bedeterministic (Type 2 channel sensing procedure). Note that Type 2channel sensing procedure includes a zero sensing duration procedure,which implies transmission within a transmission burst can start withoutchannel sensing. In one example, the directions for channel sensing maybe aligned with the directions for transmission. For example, theantenna filter configurations for channel sensing are identical to theantenna filter configurations for transmission. For yet another example,the first sensing duration within the transmission burst can be set as0. An illustration of this case is shown in FIG. 11 .

For this case, the sensing within transmission burst is performed onlywhen the sensing before the transmission burst succeeds (e.g., channelis sensed as idle).

In one example of Case-4A, the transport block in the transmission burstcan be transmitted regardless of result of associated directionalchannel sensing.

In one example of Case-4B, and the transport block in the transmissionburst can be transmitted only when associated directional channelsensing succeeds (e.g., channel for that particular direction is sensedas idle).

FIG. 12 illustrates yet another example channel access procedure 1200according to embodiments of the present disclosure. An embodiment of thechannel access procedure 1200 shown in FIG. 12 is for illustration only.

In one embodiment, a channel access procedure according to example casein this disclosure can be applicable to a transmission based on thecomposition of transmission burst. For one example, the applicablecase(s) of channel access procedure depend on the type of signal(s)and/or channel(s) included in the transmission. For another example, theapplicable case(s) of channel access procedure depend on the duration ofsignal(s) and/or channel(s) included in the transmission. For yetanother example, the applicable case(s) of channel access proceduredepend on the duty cycle of signal(s) and/or channel(s) included in thetransmission.

In one example, when the transmission burst includes discovery burstonly, the Case-3 channel access procedure can be applicable, wherein thediscovery burst can include a burst of SS/PBCH blocks, and/or configuredPDCCH and/or PDSCH of remaining minimum system information (RMSI)associated with the SS/PBCH blocks, and/or configured CSI-RS.

In one example, the Case-3A channel access procedure can be applicable,when the transmission burst includes discovery burst only. In thisexample, the discovery burst can be transmitted without channel sensingor regardless of the channel sensing result.

In one example, the Case-3C channel access procedure can be applicable,when the transmission burst includes discovery burst only. In thisexample, the transmission burst can be transmitted only when all thedirections are sensed to be idle.

In one example, the Case-3B channel access procedure cannot beapplicable, when the transmission burst includes discovery burst only.In this example, the transmission burst has to be transmitted as awhole.

In one example, when the transmission burst includes discovery burstonly, the Case-4 channel access procedure can be applicable, wherein thediscovery burst can include a burst of SS/PBCH blocks, and/or configuredPDCCH and/or PDSCH of RMSI associated with the SS/PBCH blocks, and/orconfigured CSI-RS.

In one example, the Case-4A channel access procedure can be applicable,when the transmission burst includes discovery burst only. In thisexample, the discovery burst can be transmitted without channel sensingor regardless of the channel sensing result.

In one example, the Case-4B channel access procedure cannot beapplicable, when the transmission burst includes discovery burst only.In this example, the transmission burst including discovery burst onlyhas to be transmitted as a whole.

In one example, the channel access procedure for non-unicast DLsignal(s) and/or channel(s) follows the channel access procedure fordiscovery burst, when the non-unicast signal(s) and/or channel(s) aremultiplexed with the discovery burst as one whole transmission burst.

In one example, the Case-3 channel access procedure can be applicable,when the transmission burst includes non-unicast DL signal(s) and/orchannel(s) only.

In one example, the Case-3C channel access procedure can be applicable,when the transmission burst includes non-unicast DL signal(s) and/orchannel(s) only, and if the burst of non-unicast DL signal(s) and/orchannel(s) has a QCL assumption association with a burst of SS/PBCHblocks. In this example, the transmission burst including non-unicast DLsignal(s) and/or channel(s) only has to be transmitted as a whole.

In one example, the Case-3B channel access procedure can be applicable,when the transmission burst includes non-unicast DL signal(s) and/orchannel(s) only, and if the burst of non-unicast DL signal(s) and/orchannel(s) does not have a QCL assumption association with a burst ofSS/PBCH blocks.

In one example, the Case-4 channel access procedure can be applicable,when the transmission burst includes non-unicast DL signal(s) and/orchannel(s) only.

In one example, the Case-4B channel access procedure can be applicable,when the transmission burst includes non-unicast DL signal(s) and/orchannel(s) only, and if the burst of non-unicast DL signal(s) and/orchannel(s) does not have a QCL assumption association with a burst ofSS/PBCH blocks.

In one example, the Case-3B channel access procedure can be applicable,when the transmission burst includes unicast DL signal(s) and/orchannel(s).

In one example, the Case-4B channel access procedure can be applicable,when the transmission burst includes unicast DL signal(s) and/orchannel(s).

In one example, the Case-3C channel access procedure can be applicable,when the transmission burst includes scheduled UL signal(s) and/orchannel(s).

In one example, the Case-3B channel access procedure can be applicable,when the transmission burst includes non-scheduled UL signal(s) and/orchannel(s).

In one example, the Case-4B channel access procedure can be applicable,when the transmission burst includes non-scheduled UL signal(s) and/orchannel(s).

For transmission burst in Case-3B, if a directional sensing provides asensing result as busy, the transmission segment included in thetransmission burst cannot be transmitted. Based on this channel accessprocedure, the transmission burst may not be continuous in time domain.An illustration of examples is shown in FIG. 13 .

FIG. 13 illustrates an example discontinuity in a transmission burst forchannel access 1300 procedure according to embodiments of the presentdisclosure. An embodiment of the discontinuity in a transmission burstfor channel access 1300 shown in FIG. 13 is for illustration only.

In one example, if one of the directional sensing is busy, thecorresponding transmission segment cannot be transmitted, and theresources corresponding to the transmission segment can be left asempty. An example is shown in 1301 of FIG. 13 .

In one example, the transmission burst is a downlink burst, and thesegments in the downlink burst have predefined time domain occasions fortransmission, such as at least one from SS/PBCH block, PDCCH and/orPDSCH of system information (e.g., system information block (SIBx)), orpaging.

In one example, the transmission burst is an uplink burst, and thesegments in the uplink burst have predefined time domain occasions fortransmission, such as at least one from random access channel (RACH)preambles, or a scheduled uplink transmission burst.

In one example, if one of the directional sensing is busy, thecorresponding transmission segment cannot be transmitted, and theresources corresponding to the transmission segment can be left asempty. If there are other transmission segments in the transmissionburst, a directional channel sensing corresponding to the transmissiondirection of next transmission segment is required to be performed toresume transmission. In one example, the channel sensing duration of thedirectional channel sensing deterministic (Type 2 channel sensingprocedure). An example is shown in 1302 of FIG. 13 .

In one example, the transmission burst is a downlink burst, and thesegments in the downlink burst have predefined time domain occasions fortransmission, such as at least one from SS/PBCH block, PDCCH and/orPDSCH of system information (e.g., SIBx), or paging.

In one example, the transmission burst is an uplink burst, and thesegments in the uplink burst have predefined time domain occasions fortransmission, such as at least one from RACH preambles, or a scheduleduplink transmission burst.

In one example, if one of the directional sensing is busy, thecorresponding transmission segment cannot be transmitted, and theresources corresponding to the transmission segment can be used fortransmissions with direction sensed to be idle.

In one example, the scheduling of the resources corresponding to thecancelled transmission segment can be included in a previous transmittedsegment, such as a PDCCH and/or PDSCH in the transmission segment. Anillustration of this example is shown in 1303 of FIG. 13 .

In one example, the resources corresponding to the cancelledtransmission segment can be used for transmission according to thesuccessful directions, and the scheduling information (e.g., included inDCI format carried by PDCCH) can be known to the receiver. Anillustration of this example is shown in 1304 of FIG. 13 .

For transmission burst in Case-4B, if a directional sensing provides asensing result as busy, the transmission segment included in thetransmission burst cannot be transmitted. Based on this channel accessprocedure, the transmission burst may not be continuous in time domain.An illustration of examples is shown in FIG. 14 .

FIG. 14 illustrates another example discontinuity in a transmissionburst for channel access procedure 1400 according to embodiments of thepresent disclosure. An embodiment of the discontinuity in a transmissionburst for channel access procedure 1400 shown in FIG. 14 is forillustration only.

In one example, if one of the directional sensing is busy, thecorresponding transmission segment cannot be transmitted, and theresources corresponding to the transmission segment can be left asempty. An example is shown in 1401 of FIG. 14 .

In one example, the transmission burst is a downlink burst, and thesegments in the downlink burst have predefined time domain occasions fortransmission, such as at least one from SS/PBCH block, PDCCH and/orPDSCH of system information (e.g., SIBx), or paging.

In one example, the transmission burst is an uplink burst, and thesegments in the uplink burst have predefined time domain occasions fortransmission, such as at least one from RACH preambles, or scheduleduplink transmission burst.

In one example, if one of the directional sensing is busy, thecorresponding transmission segment cannot be transmitted, and theresources corresponding to the transmission segment can be used fortransmissions with direction sensed to be idle.

In one example, the scheduling of the resources corresponding to thecancelled transmission segment can be included in a previous transmittedsegment, such as a PDCCH and/or PDSCH in the transmission segment. Anillustration of this example is shown in 1402 of FIG. 14 .

In one example, the resources corresponding to the cancelledtransmission segment can be used for transmission according to thesuccessful directions, and the scheduling information (e.g., included inDCI format carried by PDCCH) can be known to the receiver. Anillustration of this example is shown in 1403 of FIG. 14 .

FIG. 15 illustrates a flow chart of a method for adapting a channelsensing threshold according to embodiments of the present disclosure, asmay be performed by a UE (e.g., as 111-116 as illustrated in FIG. 1 )and/or BS (e.g., BS 102 in FIG. 1 ). An embodiment of the method 1500shown in FIG. 15 is for illustration only. One or more of the componentsillustrated in FIG. 15 can be implemented in specialized circuitryconfigured to perform the noted functions or one or more of thecomponents can be implemented by one or more processors executinginstructions to perform the noted functions.

In this embodiment, the method 1500 is performed in a wirelesscommunication system operating with shared spectrum channel access by aUE or BS, collectively referred to as “the device.” The method beginswith the device determining whether an antenna configuration for channelsensing is omni-directional or directional (step 1505). For example, instep 1505, if the antenna configuration for channel sensing isdetermined to be directional, the device determines one or more beamdirections for the antenna configuration and each beam direction isquasi-co-located (QCLed) with a reference signal. In some embodiments,the one or more beam directions for the antenna configuration forchannel sensing are aligned with one or more beam directions for DLtransmissions.

The device then determines a channel sensing threshold (step 1510). Forexample, in step 1510, the device may determine the channel sensingthreshold based on two parts of channel sensing threshold. A first partof the channel sensing threshold is common for omni-directional anddirectional antenna configurations. A second part of the channel sensingthreshold is dependent on the antenna configuration. In someembodiments, the second part of the channel sensing threshold is zero,if the antenna configuration is determined to be omni-directional.Additionally, the second part of the channel sensing threshold may begreater than zero, if the antenna configuration is determined to bedirectional.

Thereafter, the device performs a channel sensing procedure (step 1515).For example, in step 1515, the device performs a channel sensingprocedure to determine whether the channel is idle based on the antennaconfiguration and the channel sensing threshold. In some embodiments,the channel is determined to be idle in the channel sensing procedure,if energy detection for each beam direction of the one or more beamdirections is below the channel sensing threshold. The device thentransmits DL data over the channel (step 1520). For example, in step1520, the device transmits DL data over the channel if the channel issensed as idle in the channel sensing procedure.

The above flowcharts illustrate example methods that can be implementedin accordance with the principles of the present disclosure and variouschanges could be made to the methods illustrated in the flowchartsherein. For example, while shown as a series of steps, various steps ineach figure could overlap, occur in parallel, occur in a differentorder, or occur multiple times. In another example, steps may be omittedor replaced by other steps.

Although the present disclosure has been described with exemplaryembodiments, various changes and modifications may be suggested to oneskilled in the art. It is intended that the present disclosure encompasssuch changes and modifications as fall within the scope of the appendedclaims. None of the description in this application should be read asimplying that any particular element, step, or function is an essentialelement that must be included in the claims scope. The scope of patentedsubject matter is defined by the claims.

What is claimed is:
 1. A user equipment (UE) in a wireless communicationsystem operating with shared spectrum channel access, the UE comprising:a processor configured to: determine to transmit a transmission burstmultiplexed with multiple transmissions, wherein the multipletransmissions are with transmission beams, respectively; and perform aType 1 channel access procedure with multiple sensing beams before astart of the transmission burst, wherein each of the multiple sensingbeams corresponds to one of the transmission beams; and a transceiveroperably coupled to the processor, the transceiver configured totransmit a set of transmissions in the transmission burst after the Type1 channel access procedure, wherein a channel is sensed to be idle inthe Type 1 channel access procedure for each transmission in the set oftransmissions.
 2. The UE of claim 1, wherein an antenna filterconfiguration for a sensing beam of the multiple sensing beams isidentical to or a super set of an antenna filter configuration for atransmission beam of the transmission beams.
 3. The UE of claim 1,wherein for the Type 1 channel access procedure, a time duration spannedby sensing slots that are sensed to be idle before the start of thetransmission burst is random.
 4. The UE of claim 1, wherein: theprocessor further configured to perform a Type 2 channel accessprocedure with a sensing beam before a start of a transmission with atransmission beam within the transmission burst, and an antenna filterconfiguration for the sensing beam is identical to or a super set of anantenna filter configuration for the transmission beam.
 5. The UE ofclaim 4, wherein for the Type 2 channel access procedure, a timeduration that is sensed to be idle before the start of the transmissionis deterministic and a non-negative value.
 6. The UE of claim 1, whereinthe processor is further configured to: determine an antenna filterconfiguration for the Type 1 channel access procedure being one fromomni-directional or directional; and determine an energy detectionthreshold, wherein the energy detection threshold includes two parts: afirst part of the energy detection threshold being common foromni-directional and directional antenna filter configurations, and asecond part of the energy detection threshold depending on the antennafilter configuration.
 7. The UE of claim 6, wherein: the second part ofthe energy detection threshold is zero, if the antenna filterconfiguration is determined to be omni-directional; and the second partof the energy detection threshold is greater than zero, if the antennafilter configuration is determined to be directional.
 8. A method of auser equipment (UE) in a wireless communication system operating withshared spectrum channel access, the method comprising: determining totransmit a transmission burst multiplexed with multiple transmissions,wherein the multiple transmissions are with transmission beams,respectively; performing a Type 1 channel access procedure with multiplesensing beams before a start of the transmission burst, wherein each ofthe multiple sensing beam corresponds to one of the transmission beams;and transmitting a set of transmissions in the transmission burst afterthe Type 1 channel access procedure, wherein a channel is sensed to beidle in the Type 1 channel access procedure for each transmission in theset of transmissions.
 9. The method of claim 8, wherein an antennafilter configuration for a sensing beam of the multiple sensing beams isidentical to or a super set of an antenna filter configuration for atransmission beam of the transmission beams.
 10. The method of claim 8,wherein for the Type 1 channel access procedure, a time duration spannedby sensing slots that are sensed to be idle before the start of thetransmission burst is random.
 11. The method of claim 8, furthercomprising: performing a Type 2 channel access procedure with a sensingbeam before a start of a transmission with a transmission beam withinthe transmission burst, wherein an antenna filter configuration for thesensing beam is identical to or a super set of an antenna filterconfiguration for the transmission beam.
 12. The method of claim 11,wherein for the Type 2 channel access procedure, a time duration that issensed to be idle before the start of the transmission is deterministicand a non-negative value.
 13. The method of claim 8, further comprising:determining an antenna filter configuration for the Type 1 channelaccess procedure being one from omni-directional or directional; anddetermining an energy detection threshold, wherein the energy detectionthreshold includes two parts: a first part of the energy detectionthreshold being common for omni-directional and directional antennafilter configurations, and a second part of the energy detectionthreshold depending on the antenna filter configuration.
 14. The methodof claim 13, wherein: the second part of the energy detection thresholdis zero, if the antenna filter configuration is determined to beomni-directional; and the second part of the energy detection thresholdis greater than zero, if the antenna filter configuration is determinedto be directional.
 15. A base station (BS) in a wireless communicationsystem operating with shared spectrum channel access, the BS comprising:a processor configured to: determine to transmit a transmission burstmultiplexed with multiple transmissions, wherein the multipletransmissions are with transmission beams, respectively; and perform aType 1 channel access procedure with multiple sensing beams before astart of the transmission burst, wherein each of the multiple sensingbeams corresponds to one of the transmission beams; and a transceiveroperably coupled to the processor, the transceiver configured totransmit a set of transmissions in the transmission burst after the Type1 channel access procedure, wherein a channel is sensed to be idle inthe Type 1 channel access procedure for each transmission in the set oftransmissions.
 16. The BS of claim 15, wherein an antenna filterconfiguration for a sensing beam of the multiple sensing beams isidentical to or a super set of an antenna filter configuration for atransmission beam of the transmission beams.
 17. The BS of claim 15,wherein for the Type 1 channel access procedure, a time duration spannedby sensing slots that are sensed to be idle before the start of thetransmission burst is random.
 18. The BS of claim 15, wherein: theprocessor further configured to perform a Type 2 channel accessprocedure with a sensing beam before a start of a transmission with atransmission beam within the transmission burst, and an antenna filterconfiguration for the sensing beam is identical to or a super set of anantenna filter configuration for the transmission beam.
 19. The BS ofclaim 18, wherein for the Type 2 channel access procedure, a timeduration that is sensed to be idle before the start of the transmissionis deterministic and a non-negative value.
 20. The BS of claim 15,wherein the processor is further configured to: determine an antennafilter configuration for the Type 1 channel access procedure being onefrom omni-directional or directional; and determine an energy detectionthreshold, wherein the energy detection threshold includes two parts: afirst part of the energy detection threshold being common foromni-directional and directional antenna filter configurations, and asecond part of the energy detection threshold depending on the antennafilter configuration; wherein the second part of the energy detectionthreshold is zero, if the antenna filter configuration is determined tobe omni-directional; and wherein the second part of the energy detectionthreshold is greater than zero, if the antenna filter configuration isdetermined to be directional.